Because they belong to mice in the computer field, hear some great knowledge of God, can not wait to read the information, content will now find myself on TCP / IP four-layer structure in this resolution to share with you, I hope to give you help .
- Application Layer:
The application layer determines the communication activities of providing application services to users. TCP / IP protocol suite stored within a variety of common application services. For example, FTP (File Transfer Protocol, File Transfer Protocol) and DNS (Domain Name System, the domain name system) service is one of the two categories. Also in the HTTP protocol layer. - Transport layer
transport layer to the upper application layer, data transmission is provided between the two computers in a network connection. In a different transport layer protocols of two properties: TCP (Transmission ControlProtocol, Transmission Control Protocol) and UDP (User Data Protocol, User Datagram Protocol). - Network Layer
The network layer for processing data packets flowing on the network. Packet is a minimum data unit transmission network. This layer defines how to reach the other side of a path through a computer (a so-called transmission line), and transmits the data packets to each other. When transmission by a plurality of computers or other network device between the computer, the network layer is to choose the role of a transmission path in many options. - Link layer
link layer handles hardware portion connected to the network. It comprises a control operating system, hardware, device drivers, NIC (Network Interface Card, a network adapter, i.e. NIC), and the visible portion of the optical fiber and other physical (including all further connected to transmission media, etc.). It is visible on the hardware within the scope of the link layer.
OSI seven-layer model is just an ideal, it is generally only involves several layers of network system in which there are few systems capable of all seven layers, and fully comply with its provisions, and the four-layer structure in this article is the network the most widely used system structure.
Quoted from the article: https: //www.cnblogs.com/daijiabao/p/11183265.html
